| 摘要 |
PURPOSE:To prevent intrusion of ions into a sample and to improve the resolving power of a secondary ion mass analysis by projecting an ion beam at a low angle to a sample surface. CONSTITUTION:The ion beam 2 from a primary ion generator 1 is converged by an electron lens 3 and enters the surface of the sample 5 at a low angle theta. The secondary ions 6 sputtered by the primary ion beam 2 is drawn out by a drawing-out electrode 7 and an element distribution is measured by a mass spectrograph 12. Since the incident angle of the beam 2 on the sample surface is low, the energy perpendicular to the sample is small and the beam 2 no longer breaks down the structure of the sample 5. The greater part of the primary ions infiltrated near the surface jump out of the sample and the concn. of the primary ions in the surface is kept low. Then, the sputtering with the high resolving power with which the low incident energy and low surface ion concn. are satisfied are executed and, therefore, the resolving power of the measurement is improved. |
